1. Field of the Invention
The present invention relates to an apparatus for determining the position and condition of an object, for example the position of a blood vessel and direction in which the blood flows in this vessel, via a measuring element that is embodied as a Doppler signal emitter and receiver.
2. Description of the Prior Art
To determine the position of blood vessels or other objects, and the rate with which liquids flow therein, supersonic radiation emitters and receivers are known via which reflected Doppler frequencies can be measured. The values recorded can be evaluated without difficulty with the aid of a data-display unit.
The measuring element, which operates as an emitter and receiver, is initially manually aligned or oriented, and is then moved in a random fashion in order to locate or detect the object that is to be measured, and to receive different signals that permit appropriate conclusions to be made. Although the distance between the measuring element and a blood vessel, and hence the approximate position thereof, can be determined in this manner, it is not possible to obtain an exact measurement, since variations are essential where the random movement is carried out manually. It is also impossible to repeat the measurements with any accuracy, since the random-type movements can be reproduced only imprecisely.
It is therefore an object of the present invention to provide an apparatus of the aforementioned general type with which it is possible, with extremely straightforward means, to align or orient the measuring element and to carry out a random movement, about a predetermined point, to determine values along the x and y axes, so that it is readily possible to achieve a three-dimensional pictorial representation of the position, for example of a blood vessel, and also the direction of the blood flowing therein, since the distance is also to be determined, all this being done with the aid of the signals emitted by the measuring element. Thus a blood vessel of a patient can be measured precisely in a short period of time. The cost for such an apparatus should be kept low, and the apparatus should be easy to handle and, should be capable of being operated as easily as possible. Above all, however, it should be possible to very precisely repeat measurements and to fix the measuring element in certain positions in order to be able to repeat measurements without difficulty at a later point in time in order to determine whether any changes have occurred.